Polystachya tridentata Summerh. 1953 SECTION Superpositae

TYPE Collection Sheet by © J Bequeart and Kew's Plants of the World Website

Common Name The Three Toothed Polystachya

Flower Size

Found in Zaire, Burundi, Rwanda and Uganda, in montane forests at elevations around 2000 to 2500 meters as a small sized, cold growing epiphyte with tufted, slender, superposed, arising from the apical half of the preceding ones, narrowly cylindrical or very narrowly fusiform, smooth pseudobulbs (or annual stems) and carrying suberect, from the sheathing base oblong- or lanceolate- widely-ligulate, apex very shortly subacutely bilobed, narrowing basally, dry texture, subchartaceous, multi- nerved leaves that blooms in the spring on a simply racemose, 1.6 to 2.8" [4 to 7 cm] long overall, peduncle slender, somewhat flexuous, 1 to 1.4" [2.5 to 3.5 cm] long, rachis densely pubescent, sublaxly 3 to 9 flowered inflorescence with erect-open, narrowly lanceolate, long or caudate-acuminate, longer the the ovary floral bracts and carrying sub-erect, partly sordid red-violet partly green flowers.

"This species agrees with P. ruwenzoriensis and in the possession of hairy ovaries, but differs from P. ruwenzoriensis in the twice the larger leaves and the broadly conical sepals, and P. ugandae by twice wider leaves, larger flowers, and from both in the distinctly tridentate callus of the labellum. The most striking feature is the very broad 3-toothed labellum callus, situated just below the insertion of the middle lobe and extending on to the bases of the lateral lobes. In all allied species this callus is comparatively small and centrally placed." Summerhayes 1953

Synonyms Polystachya ruwenzoriensis var. tridentata (Summerh.) Geerinck 1988

References W3 Tropicos, Kew Monocot list , IPNI ;

* Kew Bull. 8: 133 Summerhayes 1953;

Fl. Rwanda 4: 612 Geerinck 1988 as P ruwenzoriensis var. tridentata

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